Pressing and Heating System for Pressing of a Multilayer Press Assembly

ABSTRACT

A pressing and heating system for pressing of a multilayer press assembly in which the multilayer press assembly may have a plurality of multilayer sets of material, for fabrication of printed circuit boards or the like, which are mutually separated by at least one separating plate. The system contains at least one tool that is to be inserted in an insertion opening of a stacked press. The tool being of a form that is electrically heatable, for the purpose of which heating at least one electrically powered heating element is provided, and the system further contains a control unit for controlling the heating element. With the aim of improving such a system, at least one thermocouple element is provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority, under 35 U.S.C. §119, of Germanapplications DE 10 2007 010 079.7, filed Feb. 28, 2007 and DE 10 2007054 171.8, filed Nov. 12, 2007; the prior application is herewithincorporated by reference in its entirety.

BACKGROUND OF THE INVENTION FIELD OF THE INVENTION

The invention relates to a pressing and heating system for pressing of amultilayer press assembly. The multilayer press assembly has a pluralityof multilayer sets of material being mutually separated by at least oneseparating plate. The pressing and heating system contains a stackedpress having an insertion opening, at least one electrically poweredheating element, and at least one tool for inserting into the insertionopening of the stacked press. The tool is electrically heatable by theelectrically powered heating element. A control unit is provided forcontrolling the heating element.

In the state of the art, a variety of configurations of tools, and avariety of press assembly arrangements, for the pressing of multilayerprinted circuit boards (or the like) are known. The pressing of themultilayer sets of material (for the printed circuit boards) isgenerally carried out in a stacked press under vacuum, wherewith thelayers of the respective multilayer sets are pressed together at forexample 180° C.

In general, one begins with establishment of a press assemblyarrangement which will be disposed in the press. Two press plates areemployed, designated press tools, and the elements of the multilayersets of material (for the printed circuit boards) are stacked betweenpress pads, which sets are mutually separated by separating plates. Eachmultilayer set of material (for a multilayer printed circuit board) hasa plurality of layers, namely has a plurality of interior layers andprepreg layers with copper film laminated thereon on both sides. Theresulting press assembly structure is then inserted into a press.

Published, non-prosecuted German patent application DE 10 2005 034 499 Adescribes a press assembly arrangement which has a press tool formed ofthree individual tools, each of which tools is electrically heatable.This press assembly arrangement can be inserted into the opening of astacked press. Thus a pressing and heating system is described whichrepresents a substantial improvement over the previously known state ofthe art for methods and apparatuses for pressing of multilayer pressassemblies. However, additional improvements are possible and would bedesirable.

BRIEF SUMMARY OF THE INVENTION

It is accordingly an object of the invention to provide a pressing andheating system for pressing of a multilayer press assembly thatovercomes the above-mentioned disadvantages of the prior art devices ofthis general type, which enables improved fabrication of multilayerprinted circuit boards and the like, particularly optimal energyeconomies, labor savings, and savings in fabrication costs, formultilayer printed circuit boards and the like.

With the foregoing and other objects in view there is provided, inaccordance with the invention, a pressing and heating system forpressing of a multilayer press assembly, the multilayer press assemblyhaving a plurality of multilayer sets of material being mutuallyseparated by at least one separating plate. The pressing and heatingsystem contains a stacked press having an insertion opening, at leastone electrically powered heating element, at least one thermocoupleelement, and at least one tool for being inserted into the insertionopening of the stacked press. The tool is electrically heatable by theat least one electrically powered heating element. A control unit isprovided for controlling the heating element.

The problem is solved according to the invention in that at least onethermocouple or the like is provided. By provision of one or moresensors for determining the temperature, such sensors containing inparticular thermocouples, one can appreciably improve the overallpressing and heating process for fabricating the multilayer printedcircuit boards or the like. In particular, by provision of suitablecontrol measures, the electrically heatable tools may be controlled suchthat the pressing, warming (heat-up), and heating processes can beoptimally controlled with respect to each other. High energy savings canbe achieved, and costs in time, labor, and associated costs, can befurther reduced. Thus the attendant advantages are substantial.

The above-stated problem is further solved in that the first connectingterminals and/or the associated contact connectors are configured suchthat, when the tools and/or the press assembly configuration is/areinserted into the opening of the press, a possible difference in heightbetween the first connecting terminals and the contact connectors can beautomatically compensated for, so that the first connecting terminalscan be contacted with the contact connectors. It is quite possible fordifferences in height to come about when setting up a multilayer pressassembly, particularly a press assembly formed of a plurality of sets oflayers of material to be pressed, in a so-called press assemblyconfiguration which includes the tools, wherewith among the reasons forsuch differences in height are manufacturing tolerances in fabricationof the separation plates or the multilayer sets of material themselves.This solution of providing measures for accommodating differences inheight avoids the need for extensive refitting or replacement which canbe inconvenient and costly, with the added costs including labor costs,and enables insertion of the press assembly configuration tools in theopening of a press without problems, and, without additional laborcosts, enables achievement of optimal contacting of the connectingterminals of the heating elements with the corresponding contactconnectors on the press. Not only are labor costs saved, but the timerequired to set up the press for a given operation is minimized.

In accordance with an added feature of the invention, the thermocoupleelement is disposed inside the tool. Preferably, the thermocoupleelement is one of at least three thermocouple elements and the tool isone of three tools that are insertable into the insertion opening of thestacked press, and each of the tools has a respective one of thethermocouple elements.

In accordance with an additional feature of the invention, the toolincludes a cover plate, a heat transfer plate and the heating element isdisposed between the cover plate and the heat transfer plate.Optionally, the tool includes two heat transfer plates and the heatingelement is disposed between the two heat transfer plates.

In accordance with a further feature of the invention, the heatingelement is a flattish heating body with a micanite coating on at leasttwo sides.

In accordance with another feature of the invention, the three toolsdefine a press assembly configuration having an upper tool and a lowertool constructed and disposable in relation to the at least onemultilayer press assembly. At least the upper and lower tools arecapable of being inserted and utilized in the insertion opening of thestacked press. The press assembly configuration further includes amiddle tool disposed generally in a middle of the press assemblyconfiguration.

In accordance with yet another feature of the invention, thethermocouple element is disposed in the multilayer press assembly.

In accordance with another added feature of the invention, the heatingelement is one of three heating elements and each of the heatingelements is part of one of the tools. The stacked press has firstcontact connectors and second sensor connectors and at least one of theheating elements and the tools have first electrical connectingterminals for connecting with corresponding ones of the first contactconnectors of the stacked press. The thermocouple elements havecorresponding second connecting terminals for connecting withcorresponding ones of the second sensor connectors of the stacked press.Ideally, at least one of the first and second connecting terminals areplug connectors.

With the foregoing and other objects in view there is provided, inaccordance with the invention, a pressing and heating system forpressing at least one multilayer press assembly formed of multilayersets of material. The pressing and heating system includes a pressassembly configuration containing electrically heatable tools havingfirst connecting terminals, heating elements having first connectingterminals, and a press for at least one of pressing and fabricating theat least one multilayer press assembly. The press has an opening forallowing insertion of the multilayer press assembly and insertion of theelectrically heatable tools. The press has electrical contact connectorsfor receiving the first connecting terminals of the heating elementsand/or the tools. At least one of the first connecting terminals and theelectrical contact connectors are configured such that, when at leastone of the tools or the press assembly configuration is inserted intothe opening of the press, a possible difference in height between thefirst connecting terminals and the electrical contact connectors can beautomatically compensated for, so that the first connecting terminalscan be contacted with the electrical contact connectors.

In accordance with an added feature of the invention, thermocoupleelements having second connecting terminals are provided. The press hassensor connectors each provided for a corresponding one of thethermocouple elements, the second connecting terminals and correspondingones of the sensor connectors are configured such that, when at leastone of the tools and the press assembly configuration is inserted in theopening of the press, a possible difference in height between the secondconnecting terminals and the sensor connectors can be automaticallycompensated for, so that the second connecting terminals can becontacted with the sensor connectors.

In accordance with a preferred embodiment of the invention, theelectrical contact connectors and/or the sensor connectors arerealizable in a contact strip. Ideally, the electrical contactconnectors, the sensor connectors and/or the contact strip is disposedat a rear wall of the opening of the press. Optionally, the first andsecond connecting terminals, the electrical contact connectors and thesensor connectors are in the form of sliding contact sets whichautomatically compensate for height differences. Furthermore, the firstand second connecting terminals, the electrical contact connectors andthe sensor connectors may have at least partly tapered regions and/orspring-loaded contact elements, for automatic compensation for possibleheight differences between the first and second connecting terminals,and the electrical contact connectors and the sensor connectors.Additionally, the first and/or second connecting terminals have acontact point configuration. Ideally, the contact point configuration isa knob-shaped configuration.

In accordance with another feature of the invention, each of the toolshas a connecting block for bearing and accommodating the first and/orsecond connecting terminals. Each of the connecting blocks has at leasttwo first electrical connecting terminals for a respective one of theheating elements. Preferably, the connecting blocks are also providedfor each of the thermal couple elements and each accommodate two secondconnecting terminals.

In accordance with another feature of the invention, the thermocoupleelements are plate-shaped and are inserted generally in a middle of themultilayer press assembly. Each of the thermocouple elements isassociated with at least one connecting block for accommodating two ofthe first and second connecting terminals.

In accordance with a further feature of the invention, the press haspress plates; and the electrical contact connectors and/or the sensorconnectors are disposed on at least one of the press plates. Theelectrical contact connectors and the sensor connectors correspond tothe first and/or second connecting terminals and can be brought intocontact with the first and second connecting terminals. Wherein theelectrical contact connectors and/or the sensor connectors are at leastpartially in a form of tongue members which extend vertically in amanner such as to be able to compensate for possible height differences.Ideally, the electrical contact connectors and/or the sensor connectorsare in a form of spring-loaded tongue members. The spring-loaded tonguemembers can be at least partly displaced in a horizontal direction witha compressive force.

In accordance with yet another feature according to the invention,opposing connecting blocks are provided. Each of the tools hasassociated with it a respective opposing connecting block which bears oraccommodate respective electrical contact connectors and the sensorconnectors. The opposing connecting blocks correspond to the connectingblocks. The opposing connecting blocks are disposed on or at the pressplates at different heights and with the spring-loaded tongue membershaving different heights. The opposing connecting blocks correspond tothe first and second connecting terminals of a respective tool and thethermocouple elements, such that contact between the first and secondconnecting terminals, and the electrical contact connectors and thesensor connectors, is enabled.

In accordance with an additional feature of the invention, a controlunit is provided and that during a pressing and heating process currenttemperatures of the tools and/or temperatures inside the multilayerpress assembly are measurable and measurements are sent to the controlunit. The control unit has a microprocessor, and a heating of themultilayer press assembly is controllable over time in a manner suchthat essentially uniform heating of the multilayer press assembly isenabled.

In accordance with another further feature of the invention, the presshas hydraulic actuators connected to and controlled by the control unitsuch that coordinated control of a heating and operation of thehydraulic actuators is enabled, such that at least for periods of timesimultaneous heating and control of pressure forces which prevail in thepress assembly configuration is enabled.

In accordance with the invention, each of the connecting blocks hasthree first electrical connecting terminals for a respective heatingelement, the three first electrical connecting terminals include aground terminal.

Other features which are considered as characteristic for the inventionare set forth in the appended claims.

Although the invention is illustrated and described herein as embodiedin a pressing and heating system for pressing of a multilayer pressassembly, it is nevertheless not intended to be limited to the detailsshown, since various modifications and structural changes may be madetherein without departing from the spirit of the invention and withinthe scope and range of equivalents of the claims.

The construction and method of operation of the invention, however,together with additional objects and advantages thereof will be bestunderstood from the following description of specific embodiments whenread in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a diagrammatic, side elevational view of a press assembly forarrangement in a press, wherewith tools are shown schematically as arethermocouple elements disposed in two multilayer press assembliesaccording to the invention;

FIG. 2A is a diagrammatic, side elevational view of the press assemblyin a press viewed laterally, showing thermocouple elements disposed inthe region of the tools;

FIG. 2B is a diagrammatic, perspective view of the arrangement of thepress assembly and the tools in the press, with various thermocoupleelements, and their connecting terminals and contact connectors;

FIG. 3 is a schematic lateral detail view, partially enlarged, of thearrangement of the press assembly disposed in a press, with theschematically shown connecting terminals of the thermocouple elements;

FIG. 4 is a graph showing a heating curve, intended to illustrate thecontrol of an upper and lower tool in the press assembly;

FIG. 5 is a diagrammatic, perspective view of the press assemblydisposed in the opening of a stacked press, showing the lower pressplate but with omission of the upper press plate;

FIG. 6 is a diagrammatic, rear perspective view of the press assembly,showing the individual terminals but with omission of the opposingcontact connectors in the press and with omission of the multilayerpress assemblies between the individual tools;

FIG. 7 is a diagrammatic, perspective view of the lower press plate ofthe press, with the terminals and sensor contacts also being shownschematically; and

FIG. 8 is a diagrammatic, rear view of the press assembly configurationwhich has been pushed into the opening of a press, showing the threetools, but with omission of the multilayer press assemblies, and withomission of the upper press plate of the press thus showing only thelower press plate.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the figures of the drawing in detail and first,particularly, to FIG. 1 thereof, there is shown at least partially apressing and heating system for pressing of at least one multilayerpress assembly 1 b (two such assemblies 1 b being shown here in apreferred embodiment), wherewith each multilayer press assembly 1 b hasa plurality of sets 7 of material each of which sets is formed ofmultiple layers of material to be pressed to form a multilayer printedcircuit board or the like. At least one tool 11 is provided (here thethree tools 11 a, 11 b, and 11 c, in a preferred embodiment) which comesto be inserted in or pushed into an insertion opening 3 of a press 2(here a stacked press 2 a, in a preferred embodiment), wherewith theelectrical configuration of the tool 11 (viz. the tools 11 a, 11 b, 11c) is such that each tool 11 a, 11 b, 11 c is associated with or formedof at least one electrically powered heating element 10. Anon-illustrated control unit for controlling the heating elements 10 isprovided.

The described advantages are achieved in that at least one thermocoupleor the like is provided (preferably two thermocouple elements 4, 5 (FIG.1)). The thermocouple elements 4, 5 may be in the form ofnickel-titanium elements, preferably partially of a plate-like shape,and preferably have cable-like ends which have connecting terminals 14 b(described further hereinbelow). It is also possible that thermocoupleelements 8 may be provided inside the tools 11 a-11 c, as illustratedschematically (e.g.) in FIGS. 2-3. Also possible is disposition ofthermocouple elements in the multilayer press assembly (as illustratedin FIG. 1), possibly in addition to disposition inside the tools (e.g.thermocouple elements 8 in FIGS. 2A-3). These configurations will dependon the given application situation.

As seen in FIGS. 2A-3, each tool 11 a, 11 b, 11 c preferably has arespective thermocouple element 8. The tools 11 a, 11 b, 11 c arecapable of being inserted in (pushed into) the opening 3 of the press 2.As seen in FIGS. 1-3, a central tool 11 a, an upper tool 11 b, and alower tool 11 c are provided. The upper tool 11 b and lower tool 11 care each formed of a cover plate 12, a heat transfer plate (and/or heatconduction plate) 13, and a heating element 10 disposed between theplates 12 and 13. The middle tool 11 a is formed of two heat transferplates (and/or heat conduction plates) 13 and the heating element 10disposed between the plates 13. The heat transfer and/or heat conductionplates 13 are specially constructed, with an aluminum core 13 a and twoouter plated alloy steel sheets 13 b preferably in a thickness ratio of80:20 (13 a to 13 b).

The heating elements 10 are in the form of flattish electrical heatingbodies, with a special configuration, formed of electrical heatingelements (and/or heating wires) which preferably are wound aroundassociated elements; the heading bodies are provided between twomicanite coatings. The micanite coatings serve as electrical insulatorswith respect to the thermal conduction plate 13 and the cover plate 12.

As seen from FIGS. 1-3, the upper and lower tools 11 b, 11 c areconstructed and are disposable in relation to at least one multilayerpress assembly 1 b such that a press assembly configuration 1 a isrealized, namely at least the upper and lower tools 11 b, 11 c areinsertable and usable as a press tool, in the opening of a press.Preferably, a third tool 11 a is provided generally in the middle of thepress assembly configuration 1 a, to promote good heat distribution andoptimal heating in the middle of the overall press assemblyconfiguration 1 a. The tools 11 a, 11 b, 11 c are first fabricated asseparated components, but when the press assembly configuration 1 a isbeing set up they are interconnected, via suitable guide elements,particularly guide rods and/or the like, so that the overall pressassembly configuration 1 a can be readily inserted in the opening 3 ofthe press 2, and the upper and lower tools 11 b, 11 c can then beemployed as pressing tools (or as part of a pressing tool set).

Also as seen from FIGS. 1-3, the heating elements 10 and tools 11 a, 11b, 11 c have first electrical connecting terminals 14 a for connectingto corresponding contact connectors 15 a of the press 2. Thethermocouple elements 4, 5; 8 have associated second electricalconnecting terminals 14 b for connecting to corresponding sensorconnectors 15 b (sensor contact connectors) of the press 2. The firstand/or second connecting terminals 14 a; 14 b may preferably be in theform of plug connectors, to facilitate mutual engagement of theconnector elements when the press assembly configuration 1 a is insertedinto the opening 3 of the press 2.

Preferably, the press 2 is specially adapted to serve as part of thehere illustrated pressing and heating system for pressing andfabrication of multilayer sets of material 7 for printed circuit boardsor the like, namely for pressing of the multilayer press assemblies 1 b.For this purpose, the press 2 has corresponding electrical contactconnectors 15 a for the respective heating elements 10 and tools 11 a,11 b, 11 c, and has corresponding sensor connectors 15 b for therespective thermocouple elements 4, 5; 8.

Preferably the press 2 of the described type is in the form of aheatable vacuum press. The contact connectors 15 a, 15 b are thuspreferably provided in one or more contact strips 16 disposed at a rearwall of the insertion opening 3 of the press 2.

The drawbacks described supra are further countered (alleviated) in thatthe first connecting terminals 14 a and/or the associated contactconnectors 15 a are configured such that, when the tools 11 a, 11 b, 11c and/or the press assembly configuration 1 a is/are inserted into theopening 3 of the press 2, the possible height difference between thefirst connecting terminals 14 a and the associated contact connectors 15a can be automatically compensated for, to enable contacting of theterminals 14 a with the connectors 15 a.

The second connecting terminals 14 b, of the thermocouple elements 4, 5;8, may have corresponding sensor connectors 15 b which generallycorrespond to the connecting terminals 14 b, being constructed such thatwhen the tools 11 a, 11 b, 11 c and/or the press assembly configuration1 a is/are inserted into the opening 3 of the press 2, the possibleheight difference between the second connecting terminals 14 b and theassociated sensor connectors 15 b can be automatically compensated for,to enable contacting of the terminals 14 b with the connectors 15 b.

It is possible that as a result of the layering and disposition, and/orother factors in the manufacturing, of the press assembly configuration1 a which is to be inserted in the opening 3 of the press 2, the pressassembly configuration 1 a will not always have a specific invariantheight (which will depend inter alia on sandwiched separating plates 6and multilayer sets of material 7 for printed circuit boards or thelike; therefore, one cannot predict that the connecting terminals 14 a,14 b will always be at the same height. Accordingly, the contactconnectors 15 a and sensor connectors 15 b of the press 2 which serve asengaging parts to the terminals, while they will be disposed at specificlocations in the press 2, will be specifically configured to accommodate(compensate for) such height variabilities at the time that the pressassembly configuration 1 a is inserted into the opening 3 of the press2, so as to produce suitable contacting when the tools 11 a, 11 b, 11 care so inserted, even if the press assembly configuration 1 a has any ofthe possible height variations.

One way to provide this accommodation is for the first and secondconnecting terminals 14 a, 14 b, and the contact connectors 15 a andsensor connectors 15 b, to be realized as sliding contact sets (e.g.so-called “wiping contacts”) which automatically adjust for heightdifferences. In an embodiment of this, the first and second connectingterminals 14 a, 14 b, and the contact connectors 15 a and sensorconnectors 15 b, have tapered regions, or have non-illustratedspring-loaded contact elements which serve to automatically compensatefor height differences between the first and second connecting terminals14 a, 14 b, on the one hand, and the contact connectors 15 a and sensorconnectors 15 b, on the other hand. For reliability, spring-loadedcontact elements are particularly useful.

A preferred embodiment of the first and second connecting terminals 14a, 14 b, and of the contact connectors 15 a and sensor connectors 15 b,is illustrated schematically in FIGS. 5-8.

FIG. 6 shows schematically the press assembly configuration 1 a with theindividual tools 11 a, 11 b, 11 c. The multilayer press assemblies 1 bdisposed between the tools 11 a and 11 b (and between the tools 11 a and11 c) are not shown here. FIG. 6 clearly shows a contact pointconfiguration of the first and/or second connecting terminals 14 a, 14b, particularly a knob-like configuration. Each of the tools 11 a, 11 b,11 c has a respective connecting block 17 a, 17 b, 17 c whichaccommodates the first and/or second connecting terminals 14 a, 14 b.FIG. 5 also provides a good illustration of this, in part.

The tool 11 a is associated with the connecting block 17 a, the tool 11b with the connecting block 17 b, and the tool 11 c with the connectingblock 17 c. Each connecting block 17 a, 17 b, 17 c has associatedconnecting terminals 14 a and 14 b. In particular, for each heatingelement 10 of a given tool 11 a, 11 b, 11 c, at least two firstelectrical connecting terminals 14 a, preferably three first electricalconnecting terminals 14 a (including the neutral (or ground) terminal),are provided. This is particularly well illustrated in FIG. 6. Also, foreach thermocouple element 8, the individual connecting blocks 17 a, 17b, 17 c each have two second connecting terminals 14 b (alsoparticularly well illustrated in FIG. 6.

The press assembly configuration 1 a in FIGS. 5-8 does not includedepiction of the multilayer press assemblies 1 b between the tools 11 a,11 b, 11 c, but essentially only depiction of the individual tools 11 a,11 b, 11 c with the contacts and their opposite contacts (the latterbeing particularly well shown). The thermocouple elements 4, 5 which areillustrated in FIG. 1 are also accommodated, which thermocouple elements4, 5 have generally flat shapes and can be disposed generally in themiddle of a multilayer press assembly 1 b. In the preferred embodiment,only one plate-like thermocouple element 5 is provided in the pressassembly configuration 1 a, namely in the lower multilayer pressassembly 1 b which commonly is disposed between the middle and lowertools 11 a and 11 c. The plate-like thermocouple element 5 has aconnecting block 18, and preferably has two connecting blocks 18 a, 18b, each with a second connecting terminal 14 b—also well illustrated inFIG. 6.

As seen from FIGS. 5, 7, and 8, the press 2 has contact connectors 15 aand sensor connectors 15 b that correspond to the first and secondconnecting terminals 14 a; 14 b, which connectors 15 a; 15 b can bebrought into compressive contact with the terminals 14 a; 14 b. Thesecontact connectors 15 a and sensor connectors 15 b are preferablydisposed on at least one of the press plates 2 b or 2 c of the press 2.It is possible, however, for the contact connectors 15 a and sensorconnectors 15 b to be disposed on the side wall and/or rear wall of thepress 2. The configuration will depend on the given applicationsituation, and on the forms of the connecting terminals 14 a, 14 b onthe tools 11.

The form and disposition of the contact connectors 15 a and sensorconnectors 15 b is readily seen from FIGS. 5, 7, and 8. In order tocompensate for a possible height difference, these connectors 15 a; 15 bare at least partly in the form of tongue members which extendvertically (see especially FIG. 7, which shows only the connectors 15 a;15 b associated with the lower press plate 2 c of the press 2, in afront view, in the absence of the tools 11 a, 11 b, 11 c which are to beinserted into the press. It is also well illustrated how the contactconnectors 15 a and sensor connectors 15 b are in the form ofspring-loaded tongue members (preferably formed of spring steel). Thespring-loaded tongue members are fixed in connecting blocks 19 a, 19 b,19 c, via the lower ends of the tongue members, preferably with the aidof screw elements. The tongue members 15 a; 15 b and associated screwelements are not shown in pictorial detail; however, they are realizedin a form such that the spring-loaded tongue members, particularly theirupper ends, are mounted so as to be displaceable (e.g. slidable) atleast partially in the horizontal direction, with a compressive force inthe opposing connecting blocks 19 a, 19 b, 19 c, as seen from FIGS. 5and 7, in that the blocks 19 a, 19 b, 19 c are configured to havecorresponding recesses on the side and direction facing the tools 11 a,11 b, 11 c which enable such displaceability in the horizontaldirection.

Thus, opposing connecting blocks 19 a, 19 b, 19 c are provided which areopposed to the connecting blocks 17 a, 17 b, 17 c of the tools 11 a, 11b, 11 c, which opposing blocks 19 a, 19 b, 19 c are disposed on thepress 2, preferably on one of the pressure plates 2 b, 2 c. The numberof contact connectors 15 a and sensor connectors 15 b provided in theopposing connecting blocks 19 a, 19 b, 19 c corresponds to the (numberof) first and second connecting terminals 14 a, 14 b—which also isclearly seen from the figures. Preferably, the middle opposingconnecting block 19 a has two additional (outer) sensor connectors 15 b,15 b for the second connecting terminals 14 b of the thermocoupleelement 5, as seen particularly well from FIG. 5.

As clearly seen (however schematically) from FIGS. 5, 7, and 8, theopposing connecting blocks 19 a, 19 b, 19 c are disposed on press plate2 c at essentially different heights and with different lengths, and thespring-loaded springs have corresponding different heights, so that thevarious contact connectors 15 a and sensor connectors 15 b which engagethe first and second connecting terminals 14 a; 14 b of the respectivetools 11 a; 11 b are continuously in good alignment. In particular, thelengths of the spring-loaded tongue members are such that heightdifferences (tolerances) which can arise as a result of, e.g., themakeup of the press assembly configuration 1 a can be compensated for,particularly so as to provide a good contact between the respectivecontact elements, even in the event of variations in the press assemblyarrangements 1 a, in particular because the lengths of the spring-loadedtongue members are such as to accommodate the tolerances. Preferably,the press 2 is in the form of a stacked press with a plurality ofopenings 3 (so-called “stages”, or “levels”), with contact connectors 15a and sensor connectors 15 b being disposed at each stage (or level) ofthe stack.

During the pressing and heating process, the current temperatures of thetools 11 a, 11 b, 11 c are measured, and/or the temperatures inside themultilayer press assembly 1 are measured, and the measurements areforwarded to the non-illustrated control unit. Preferably, the controlunit has a microprocessor, and the timewise heating of the multilayerpress assembly 1 b is controllable so as to enable uniform heating ofthe “book” and of the multilayer press assembly 1 b.

FIG. 4 shows a representative heating curve, e.g. for ten multilayersets of material having six layers (for fabrication of printed circuitboards or the like), namely the heating of a lower and upper tool in apress assembly and the heating of the book in the middle, versus time(in seconds) (with the temperature as well as pressure being plotted onthe vertical axis). It is seen that the lower and upper tools 11 b, 11 care heated essentially equally, and it is seen how the book in themiddle is heated with a regular lag after the tools. Also readily seenis that, beginning at a certain time, here preferably after fiveminutes, the pressing process is started, with the relevant pressingpressure being applied in the press 2.

Accordingly, the control unit is configured such that the hydraulicactuators of the press are controllable depending on the course of thetemperature inside the press assembly configuration 1 a, enabling acoordinated form of simultaneous control of both the heating and theapplication of the hydraulic actuators (control of the pressing force),so that, at least for a period of time (as illustrated in FIG. 4), onecan carry out heating and can simultaneously adjust the pressure. Thissaves energy (and thus energy-related costs), shortens the operatingtime, and reduces the operating costs, for fabricating the multilayerproducts (printed circuit boards or the like), in a decisivelyadvantageous manner. Controlled supply of energy is enabled, as isquality control during the pressing process, in particular via theplotting and evaluation of the heating curve.

Finally, old presses that have, e.g., channels 9, can be easily andquickly retrofitted to utilize the inventive pressing and heatingsystem.

1. A pressing and heating system for pressing of a multilayer pressassembly, the multilayer press assembly having a plurality of multilayersets of material being mutually separated by at least one separatingplate, the pressing and heating system comprising: a stacked presshaving an insertion opening formed therein; at least one electricallypowered heating element; at least one tool for being inserted into saidinsertion opening of said stacked press, said tool being electricallyheatable by said at least one electrically powered heating element; acontrol unit for controlling said heating element; and at least onethermocouple element.
 2. The pressing and heating system according toclaim 1, wherein said thermocouple element is disposed inside said tool.3. The pressing and heating system according to claim 1, wherein: saidthermocouple element is one of at least three thermocouple elements; andsaid tool is one of three tools that are insertable into said insertionopening of said stacked press, and each of said tools has a respectiveone of said thermocouple elements.
 4. The pressing and heating systemaccording to claim 1, wherein said tool includes a cover plate, a heattransfer plate and said heating element disposed between said coverplate and said heat transfer plate.
 5. The pressing and heating systemaccording to claim 1, wherein said heating element is a flattish heatingbody with a micanite coating on at least two sides.
 6. The pressing andheating system according to claim 3, wherein said three tools define apress assembly configuration having an upper tool and a lower toolconstructed and disposable in relation to the at least one multilayerpress assembly, at least said upper and lower tools are capable of beinginserted and utilized in said insertion opening of said stacked press,said press assembly configuration further includes a middle tooldisposed generally in a middle of said press assembly configuration. 7.The pressing and heating system according to claim 1, wherein saidthermocouple element is disposed in the multilayer press assembly. 8.The pressing and heating system according to claim 3, wherein: saidheating element is one of three heating elements and each of saidheating elements is part of one of said tools; said stacked press hasfirst contact connectors and second sensor connectors; at least one ofsaid heating elements and said tools have first electrical connectingterminals for connecting with corresponding ones of said first contactconnectors of said stacked press; and said thermocouple elements havecorresponding second connecting terminals for connecting withcorresponding ones of said second sensor connectors of said stackedpress.
 9. The pressing and heating system according to claim 8, whereinat least one of said first and second connecting terminals are plugconnectors.
 10. The pressing and heating system according to claim 1,wherein said tool includes two heat transfer plates and said heatingelement is disposed between said two heat transfer plates.
 11. Apressing and heating system for pressing at least one multilayer pressassembly formed of multilayer sets of material, the pressing and heatingsystem comprising: a press assembly configuration containingelectrically heatable tools having first connecting terminals; heatingelements having first connecting terminals; and a press for at least oneof pressing and fabricating the at least one multilayer press assembly,said press having an opening formed therein in for allowing insertion ofthe multilayer press assembly and insertion of said electricallyheatable tools, said press having electrical contact connectors forreceiving said first connecting terminals of one of a given one of saidheating elements and a given one of said tools, at least one of saidfirst connecting terminals and said electrical contact connectors areconfigured such that, when at least one of said tools or said pressassembly configuration is inserted into said opening of said press, apossible difference in height between said first connecting terminalsand said electrical contact connectors can be automatically compensatedfor, so that said first connecting terminals can be contacted with saidelectrical contact connectors.
 12. The pressing and heating systemaccording to claim 11, further comprising thermocouple elements havingsecond connecting terminals; and wherein said press has sensorconnectors each provided for a corresponding one of said thermocoupleelements, said second connecting terminals and corresponding ones ofsaid sensor connectors are configured such that, when at least one ofsaid tools and said press assembly configuration is inserted in saidopening of said press, a possible difference in height between saidsecond connecting terminals and said sensor connectors can beautomatically compensated for, so that said second connecting terminalscan be contacted with said sensor connectors.
 13. The pressing andheating system according to claim 11, wherein at least one of saidelectrical contact connectors and said sensor connectors are realizablein a contact strip.
 14. The pressing and heating system according toclaim 13, wherein at least one of said electrical contact connectors,said sensor connectors and said contact strip is disposed at a rear wallof said opening of said press.
 15. The pressing and heating systemaccording to claim 12, wherein said first and second connectingterminals, said electrical contact connectors and said sensor connectorsare in the form of sliding contact sets which automatically compensatefor height differences.
 16. The pressing and heating system according toclaim 12, wherein said first and second connecting terminals, saidelectrical contact connectors and said sensor connectors have at leastone of at least partly tapered regions and spring-loaded contactelements, for automatic compensation for possible height differencesbetween said first and second connecting terminals, and said electricalcontact connectors and said sensor connectors.
 17. The pressing andheating system according to claim 12, wherein at least one of said firstand second connecting terminals have a contact point configuration. 18.The pressing and heating system according to claim 12, wherein each ofsaid tools has a connecting block for bearing and accommodating at leastone of said first and second connecting terminals.
 19. The pressing andheating system according to claim 18, wherein each of said connectingblocks has at least two said first electrical connecting terminals for arespective one of said heating elements.
 20. The pressing and heatingsystem according to claim 18, wherein said connecting blocks are alsoprovided for each of said thermal couple elements and each accommodatetwo of said second connecting terminals.
 21. The pressing and heatingsystem according to claim 18, wherein said thermocouple elements areplate-shaped and are inserted generally in a middle of the multilayerpress assembly, each of said thermocouple elements is associated with atleast one said connecting block for accommodating two of said first andsecond connecting terminals.
 22. The pressing and heating systemaccording to claim 18, wherein: said press has press plates; and atleast one of said electrical contact connectors and said sensorconnectors are disposed on at least one of said press plates, saidelectrical contact connectors and said sensor connectors correspond toat least one of said first and second connecting terminals and can bebrought into contact with said first and second connecting terminals.23. The pressing and heating system according to claim 12, wherein atleast one of said electrical contact connectors and said sensorconnectors are at least partially in a form of tongue members whichextend vertically in a manner such as to be able to compensate forpossible height differences.
 24. The pressing and heating systemaccording to claim 22, wherein at least one of said electrical contactconnectors and said sensor connectors are in a form of spring-loadedtongue members.
 25. The pressing and heating system according to claim24, wherein said spring-loaded tongue members can be at least partlydisplaced in a horizontal direction with a compressive force.
 26. Thepressing and heating system according to claim 24, further comprisingopposing connecting blocks, each of said tools has associated with it arespective one of said opposing connecting blocks which bear oraccommodate respective ones of said electrical contact connectors andsaid sensor connectors, said opposing connecting blocks correspond tosaid connecting blocks.
 27. The pressing and heating system according toclaim 26, wherein said opposing connecting blocks are disposed on or atsaid press plates at different heights and with said spring-loadedtongue members having different heights, said opposing connecting blockscorresponding to at least one of said first and second connectingterminals of a respective one of said tools and said thermocoupleelements, such that contact between said first and second connectingterminals, and said electrical contact connectors and said sensorconnectors, is enabled.
 28. The pressing and heating system according toclaim 12, further comprising a control unit and that during a pressingand heating process at least one of current temperatures of said toolsand temperatures inside said multilayer press assembly are measurableand measurements are sent to said control unit.
 29. The pressing andheating system according to claim 28, wherein said control unit has amicroprocessor, and a heating of the multilayer press assembly iscontrollable over time in a manner such that essentially uniform heatingof the multilayer press assembly is enabled.
 30. The pressing andheating system according to claim 28, wherein said press has hydraulicactuators connected to and controlled by said control unit such thatcoordinated control of a heating and operation of said hydraulicactuators is enabled, such that at least for periods of timesimultaneous heating and control of pressure forces which prevail insaid press assembly configuration is enabled.
 31. The pressing andheating system according to claim 11, wherein said contact pointconfiguration is a knob-shaped configuration.
 32. The pressing andheating system according to claim 18, wherein each of said connectingblocks has three first electrical connecting terminals for a respectiveone of said heating elements, said three first electrical connectingterminals include a ground terminal.
 33. The pressing and heating systemaccording to claim 21, wherein each of said thermocouple elements isassociated with two of said connecting blocks.
 34. The pressing andheating system according to claim 22, wherein said first and secondconnecting terminals can be brought into compressive contact with saidfirst and second connecting terminals.
 35. The pressing and heatingsystem according to claim 24, wherein at least one of said electricalcontact connectors and said sensor connectors is formed from springsteel.